A fundamental claim of biofield therapies is that energy is emitted by the practitioner and received by the patient (recipient). However, there are no laboratory studies attempting to examine psychophysiological and biophysical effects of biofield mechanisms in practitioners and recipients simultaneously. As part of the Center for Frontier Medicine in Biofield Science, this three year exploratory project applies established psychophysiological measures (primary measures: heart rate variability, laboratory and 24 hour; and EEG spectral analyses) as well as innovative biophysical measures (secondary measures: dynamic ECG-EEG synchrony; tertiary measures: high frequency X ray emission, and gamma ray absorption and / or scattering), to test biofield predictions that are hypothesized to discriminate between (1) an emitting biofield therapy (Johrei) and (2) a receiving bjofield therapy (Yan Xin Qigong). Two studies (Study 1:Cross-sectional; Study 2: Prospective) compare practitioners of Johrei therapy and Yan Xin Qigong with matched controls. Practitioners of Johrei (developed in Japan) and Yan Xin Qigong (developed in China) are committed to Western research and evidence-based medicine. Johrei and Qigong both believe that practitioners receive energy from the environment. However, the intention of Johrei therapy is primarily for practitioners to heal others (e.g. patients), whereas the intention of Yan Xin Qigong is primarily to help practitioners heal themselves. Study 1 compares experienced Johrei practitioners (N=32) with Qigong practitioners (N=32), and age and sex matched controls (N=32). The design includes examining psychophysiological and biophysical measures during pre-post resting conditions as well as during the practice of Johrei, the practice of Qigong, or the practice of a simple relaxation-response in nonpractitioner controls. It is hypothesized that the practice of Johrei and Qigong will be associated with increased heart rate variability and EEG alpha-theta (primary measures) compared to the relaxationresponse controls. However, based on previous innovative findings, increased ECG-EEG synchrony, increased high frequency X ray emission, and increased gamma ray absorption / scattering effects arc expected in the Johrei Group compared to the Qigong group. Study 2 replicates Study I using a prospective design: beginners will be tested before and after four months of Johrei training (N=32), and compared with four months of Qigong training (N=32) versus a group of matched waiting list controls (N=32). It is hypothesized that findings from Study 1 will he replicated following four months of training (Study 2). These basic science laboratory studies will be the first to explore possible psychophysiological and biophysical mechanisms in biofield therapies. These studies will advance the scientific foundations of the biofield concept and biofield therapeutics.